A British man suspected of hacking into 53 Nasa (National Aeronautics and Space Administration) and US military networks is facing extradition today.

Gary McKinnon, 39, an unemployed man from north London, was arrested by officers from the Metropolitan Police Service Extradition Unit on Tuesday night and taken to a police station in the capital.

McKinnon, known as 'Solo' in the hacking world, is appearing in custody today at Bow Street Magistrates Court on an extradition warrant, on behalf of the US government. The warrant says he gained illegal access and made unauthorised modifications to 53 computers belonging to the US government, including computers from the Department of Defense and the National Security Agency, between February 2001 and March 2002.

The US government has said Mckinnon's hacking caused downtime and personnel costs of $1m.

If extradited and found guilty in the US, he faces five years in prison for eight crimes he was indicted for in 2002. Among the charges, McKinnon is suspected of stealing administrator identities, deleting 1,300 user accounts and copying a file containing usernames and encrypted passwords.